Hello My name is Christine and I am the owner of Brighter Homes, the local Solatube Premier Dealership. I would be happy to set a time to discuss the features and benefits of a Solatube Daylighting System in detail. In the meantime I did want to clarify the inaccurate information that was posted in response to your question. I have never had a customer complaint that either the Effect Lens or the Diffuser discolor over time; furthermore, I called Solatube International and was told they do not have a problem with discoloration of the lens. Next, considering the climate in Virginia there should not be a problem with condensation however Solatube Daylighting Systems are designed to allow some air transfer from the interior of the system to the exterior. This allows moist air to escape, while also enabling any droplets of water, which may have formed on the dome, to escape via weep holes in the dome. Solatube Daylighting Systems is by far the best product on the market with four patents on the technology that the competition does not have. Our product has patents on Spectralight Infinity Tubing that is 99.7% highly relective, the LightTracker Reflector inside the dome, the Raybender technology of the dome and the Dual Lens Array. Please check out our website for a more complete discussion of the patented technology that Solatube Daylighting Systems have. Please do not hesitate to call me for more information at 460-0703 Here is a link that might be useful: Hampton Roads Daylight

Your Craftsman Bungalow is among the finest style homes out there. I've worked on many bungalows. Although the room is small, your plan to line up the skylight just in front of the picture window is a wonderful idea. It will look professionally planned after your done. The Velux motorized unit is dependable and long lasting. Usually, the glass will fail before the motor goes. I've replaced the Velux glass a few times. I think you got a good plan should proceed. All the best, The Porch Guy

These folks should be able to help you. Here is a link that might be useful: Velux Skylites

If the flashing on the existing curb was fine, you would not want to disturb it as a normal procedural process (assuming the curb size is correct for the new unit). Every home is different. I suggest you get a relative humidity gauge and see where your levels are and what the levels are inside the skylight shaft. That will take all the guess work out of the questions you are having. Amazon has them and I have used this one: https://www.amazon.com/RockyMars-Temperature-Humidity-Monitor-Hygrometer/dp/B01M3Q2T21/ref=sr_1_12?s=home-garden&ie=UTF8&qid=1500913462&sr=1-12&keywords=humidity+gauge  As a general observation, the tighter homes and installations will have more issues with humidity. If you neighbor's homes are getting more unintentional ventilation (i.e. doors opening and closing), the humidity level could still be higher in your home.